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In movies, hacking is all finesse, excitement, and genius coding, but in reality it's angelheaded
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hipsters burning for the ancient heavenly connection to the starry dynamo in the machinery
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of night.
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-- Ginsberg.
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Hey there Zero Cools, Neos and Seatec astronomers, I'm Trace.
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Thanks for tuning in for some DNews.
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Passwords are like apples in a fictional garden, they're perfect, ripe, and there for the taking,
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if you know how.
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Websites have a lot of different ways to store passwords, hashing, salting, tokens, two-factor
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authentication -- we have a whole video about it -- but hacking a password?
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That's a lot more fun, right?
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So first, for n00bs, passwords aren't stored as words, but as a set of encrypted characters
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called hashes.
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They look like this.
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If I want to access your account, I don't really need your password, I just have to
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find the thing that lets me decrypt that hash!
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To do that, hacker communities created 'lookup tables' and 'rainbow tables' -- data files
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of common passwords that are pre-hashed.
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Password123 hashed is this.
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abcde12345 hashed, is this.
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If a hacker did this beforehand, and has millions of passwords, they just compare them and they
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can get access to your account.
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And hackers can do this comparison really fast.
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In a test for Ars Technica, a computer could try 350 billion combinations every second!
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350 billion password guesses.
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Every.
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Second.
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How common does your password feel now?
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But companies have a weapon against rainbow tables -- it's called "salt!"
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Not like literal salt.
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It's basically taking random chunks of code and tossing them into the hashed password.
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As our AP Donna says, "It changes the flavor."
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If salted hashes are found, the rainbow tables are useless, they'll never find a match!
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Computers aren't great at problem solving, so even this little change can fumble automated
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hacking programs.
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Without the tables, everything takes longer.
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Hackers have to find out how the salt was added -- beginning of each password?
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After the 15th character?
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Is it different for every user?
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Then they have to figure out what the salt characters are, one encoder bcrypt puts $2a$
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at the beginning of every hash…
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But usually, salted passwords are enough to stop a lot of hackers, because it's faster
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to change tack and use dictionary attacks or brute force attacks -- these were made
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famous in Mr. Robot.
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Dictionary attacks use wordlists to take common passwords, like Password123, and just try
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them out.
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They salt and hash them on the fly, and compare them to passwords in the database at the speed
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of light.
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Brute force attacks are even more crazy, starting with say, "aaaa" salted hashing it various
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ways and then compare those to the database, then "aaab," then "aaac..." you get it.
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They just try every possible combination.
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It takes FOREVER.
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Sidebar: and this is why randomly generated passwords don't always help.
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In a 2014 study done for DARPA by a security company, half of our "random" passwords use
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the same five patterns to construct that "randomization."
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Because nothing's actually random -- we have a video about it.
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Hackers know this and just copy those methods and add them to the pile of known passwords.
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When it comes to simple text, computers are wicked fast.
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A hacker doing a test for Ars Technica cracked over 10,000 passwords in 16 minutes just trying
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combinations at random within the password specifications (less than 8 characters, capital
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letter, lowercase letter, et cetera).
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Hackers are in a constant race against time, not necessarily because the Feds are right
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over their shoulder like in the movies, but because once a company or agency realizes
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they've been hacked, they usually adjust security and go public, encouraging users to change
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their passwords.
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Which is why hackers just hack YOU.
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If you're on an open wifi network without a password, you're basically shouting your
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passwords for anyone listening to hear.
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Some hackers will set up fake "Free WiFi" points to get common passwords and email addresses.
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Still, others just use spam!
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If you click on a word document or link in an email, it can execute code on your computer,
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called malware, to copy everything you type (including passwords, credit card numbers
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and so on) and send it direct to the hacker.
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And still, others pose as Facebook security, or as a representative of the bank, or as
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the IT department… some will CALL YOU ON THE PHONE.
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Never EVER give someone your password EVER.
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If they're the company, they already have it!
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Why spend all that time hacking a server if I can just trick you into telling me your
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password?
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The moral of the story, other than hacking is crazy interesting…
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Is to use long, complicated passwords.
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And never use the same one twice.
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Long passwords are harder for dictionary and wordlist-based attacks to solve quickly.
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It's actually less important to use Passwords where letters are numbers -- but instead use
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a long set of words…
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Like "correct horse battery staple" or song lyrics -- easy to remember, but so long it
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would take a hacking program years of computing time to guess!
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It's sort of like that old joke about running from a bear, you don't have to have to be
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the fastest, you just don't want to be the slowest.
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If you haven't check out the other video we just did about hacking and passwords, do that
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right here.
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And let us know down in the comments if you just changed your password, because I know
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I did after this.
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Thanks for tuning in to DNews, please subscribe and come back soon.